Shimano so cup and cone. The bearing surface on the hub is likely knackered and its not replaceable. You can probably strip it all apart, clean and regrease to get a working wheel but it'll be forever grumbly.

Unless the hub bearing surface isn't damaged (unlikely), I'd just use what you've got, no point putting new cones in if the hub surface is damaged. Take it apart and have a look, it should be fairly obvious if there's pitting or damage to the surfaces that the balls touch. Mind you, if you don't have a cassette tool, big allen key and cone spanners, it might be cheaper/better to consign them to the bin. For cheap a replacement, see here: Merlin or buy new wheels with cartridge bearings which you can replace when dead.

Cheers, I will go grab the wheel and have a look, all i have noticed is that it says shimano deore on the hub but will look for a M... code.

I have a set of allen keys on me now and my multitool, my cassette tool is at home which i can pick up tomorrow. Do i need cone spanners or will any small adjustable work?

What is a centre lock hub exactly?

The spokes and rim are in good condition but are standard to the bike and are nothing special (bontranger).
I've never built a wheel up so if i need a new hub will have to visit the LBS to be built up, which could be fairly costly vs buying a new wheel set.

I have the 10mm allen key but cant get into the hub without the cassette tool so will have to wait until tomorrow before i can strip it.

The hub is a HB-M535.

I've taken a few photo's, i managed to get the dropout and cone off by hand while i was out but now the dropout is stuck and i don't have spanners with me. I took the cone off and 2 or the balls were shattered, there doesn't appear to be a great deal of damage but i can't really see properly until its all apart.

The dropout does look off centre looking from the disc side, do you think its repairable or new wheel time?

Sorry, popped out for a ride there. Its a long time since I worked on Shimano hubs so can't quite figure it out, has that bit in your hand sheared off? Tech doc here I think. The bit in your hand looks like part of the cup and if so the 'silver' damage is enough for it to run rough forever more. If I'm seeing things correctly, sheared cup with damaged surfaces and shattered balls, I'd say its time to consign the wheel to the parts bin. It probably can be fixed but if you try to find the parts (as opposed to buying a complete hub to raid), I can't see you fixing it by next weekend. The parts will probably be hard to find.

The part in his hand is the shield on the hub (not shown separately in Shimano's parts diagram).

You really need to check the condition of the cones and cups. Cones are not worth replacing, a new hub can probably be bought for the same amount. Cups can't really be replaced (yes, your can knock the old ones out and put ones from a new hub in, but it's so much easier to just lace up a new hub!).

I have taken the hub apart and cones are fine. One side does have some minor hairline cracks in the cup but I am just going to replace the bearings for now. When the hub finally goes I will work out whether the hub is worth replacing or whether to bin it.

LBS only had some 1/4" bearings for the rear hub so I need to find some 3/16" bearings. Does it matter whether I buy some hardened bearings or stainless steel? I assume stainless steel will break up easier buy may help the hub last a little longer?

Daveh I was a little confused about the shield, most deore types do look a little different!

Stainless steel is softer, chromed steel bearings are harder and preferable in this instance. Just buy whatever your local bike shop has? You won't notice a great difference either way really, just keep on top of the maintenance.